In one of its aspects, the present invention relates to a radiation source assembly. In another of its aspects, the present invention relates to a radiation source module comprising a novel radiation source assembly having incorporated therein an optical radiation sensor.
Optical radiation sensors are known and find widespread use in a number of applications. One of the principal applications of optical radiation sensors is in the field of ultraviolet radiation fluid disinfection systems.
It is known that the irradiation of water with ultraviolet light will disinfect the water by inactivation of microorganisms in the water, provided the irradiance and exposure duration are above a minimum xe2x80x9cdosexe2x80x9d level (often measured in units of microWatt seconds per square centimeter). Ultraviolet water disinfection units such as those commercially available from Trojan Technologies Inc. under the tradenames UV700 and UV8000, employ this principle to disinfect water for human consumption. Generally, water to be disinfected passes through a pressurized stainless steel cylinder which is flooded with ultraviolet radiation. Large scale municipal waste water treatment equipment such as that commercially available from Trojan Technologies Inc. under the trade-names UV3000 and UV4000, employ the same principal to disinfect waste water. Generally, the practical applications of these treatment systems relates to submersion of treatment module or system in an open channel wherein the wastewater is exposed to radiation as it flows past the lamps. For further discussion of fluid disinfection systems employing ultraviolet radiation, see any one of the following:
U.S. Pat. No. 4,482,809,
U.S. Pat. No. 4,872,980,
U.S. Pat. No. 5,006,244,
U.S. Pat. No. 5,418,370,
U.S. Pat. No. 5,539,210, and
U.S. Pat. No. 5,590,390.
In many applications, it is desirable to monitor the level of ultraviolet radiation present within the water under treatment In this way, it is possible to assess, on a continuous or semi-continuous basis, the level of ultraviolet radiation, and thus the overall effectiveness and efficiency of the disinfection process.
It is known in the art to monitor the ultraviolet radiation level by deploying one or more passive sensor devices near the operating lamps in specific locations and orientations which are remote from the operating lamps. These passive sensor devices may be photodiodes, photoresistors or other devices that respond to the impingent of the particular radiation wavelength or range of radiation wavelengths of interest by producing a repeatable signal level (in volts or amperes) on output leads.
Conventional ultraviolet disinfection systems often incorporate arrays of lamps immersed in a fluid to be treated. Such an arrangement poses difficulties for mounting sensors to monitor lamp output. The surrounding structure is usually a pressurized vessel or other construction not well suited for insertion of instrumentation. Simply attaching an ultraviolet radiation sensor to the lamp module can impede flow of fluid and act as attachment point for fouling and/or blockage of the ultraviolet radiation use to treat the water. Additionally, for many practical applications, it is necessary to incorporate a special cleaning system for removal of fouling materials from the sensor to avoid conveyance of misleading information about lamp performance.
It would be desirable to have a radiation source assembly and module containing same which incorporated an optical radiation sensor that does not interfere with the flow of water or exposure of the fluid being treated to radiation.
It is an object of the present invention to provide a novel radiation source module which obviates or mitigates at least one of the above-mentioned disadvantages of the prior art.
It is another object of the present invention to provide a novel radiation source assembly which obviates or mitigates at least one of the above-mentioned disadvantages of the prior art.
Accordingly, in one of its aspects, the present invention provides a radiation source module for use of fluid treatment system, the module comprising:
a frame having a first support member;
at least one radiation source assembly extending from and in engagement (preferably sealing engagement) with a first support member, the at least one radiation source assembly comprising at least one radiation source disposed within a protective sleeve; and
an optical radiation sensor disposed within the protective sleeve.
In another of its aspects, the present invention provides a radiation source assembly for use in a radiation source module, the radiation source assembly comprising at least one radiation source and an optical radiation sensor, both the at least one radiation source and the optical radiation sensor being disposed within a protective sleeve.
In yet another of its aspects, the present invention provides a fluid treatment system comprising:
a fluid treatment zone;
at least one radiation source assembly disposed in the fluid treatment zone, the at least one radiation source assembly comprising at least one radiation source disposed within a protective sleeve; and
an optical radiation sensor disposed within the protective sleeve.
In a preferred embodiment of the fluid treatment system, the fluid treatment zone comprises a housing through which fluid flows. Preferably, the at least one radiation source assembly is secured to the housing.
Thus, the present inventor has discovered that, by placing an optical radiation sensor within a protective sleeve commonly employed in combination with a radiation source, a number of advantages accrue. For example, the need to periodically clean the surface of the sensor from fouling materials is obviated since the sensor is disposed within the protective sleeve. This is particularly advantageous when the radiation source assembly is used in conjunction with a cleaning system (e.g., one of the cleaning systems in the xe2x80x2370, xe2x80x2210 and/or xe2x80x2390 patents referred to above). Specifically, since the cleaning system serves the purpose of removing fouling materials from the protective sleeve to allow for optimum dosing of radiation, a separate cleaning system for the sensor is not required. Further, since the optical radiation sensor is disposed within an existing element (the protective sleeve) of the radiation source module, incorporation of the sensor in the module does not result in any additional hydraulic head loss and/or does not create a xe2x80x9ccatchxe2x80x9d for fouling materials. Other advantages will be apparent to those skilled in the art.